At present lung cancer is considered to be one of the most important causes of death, especially in adults at the ages from 50 to 69 years old. Long term exposure to smoking is the cause of lung cancer for 90% of the cases. Among male smokers, the lifetime risk of developing lung cancer is about 17%; among female smokers the risk is about 11%. For non-smokers, the risk of developing lung cancer is about 1%. The main causes for lung cancer in non-smokers are genetic factors, radon gas, asbestos, air pollution and passive smoking. There are two main types of lung cancer: non-small cell lung cancer (NSCLC) (in about 80% of the cases) and small cell lung cancer (in about 17% of the cases). NSCLC can further be classified according to the growth type and spread of the cancer cells. NSCLC can therefore be classified into squamous cell carcinoma, large cell carcinoma and adenocarcinoma. Adenocarcinoma is more frequent in women, Asians and non-smokers. Other less common types of NSCLC are pleomorphic, carcinoid tumor, salivary gland carcinoma, and unclassified carcinoma.
It is generally known that most types of lung cancer have a poor prognosis. The 5 year survival for small cell lung cancer is less than 5%. Numbers are better for NSCLC. When the tumor is detected when it is still small and has not spread to the lymph nodes (Stage IA), the 5 year survival is 60%. This number drops rapidly with increasing size of the tumor and lymph node involvement. An early detection prior to the metastasis of the tumor is therefore very important, especially since at an early stage the tumor may be removed entirely by resection. However, about 50% of non-small cell lung cancer cases are only detected after metastasis. In these cases the 5-year survival of NSCLC is only 10 to 15%. Even when NSCLC is detected at an early stage, the 5-year survival rate of the patients is low compared to other types of cancer. Even more, it is known that long-term (>5 years) NSCLC patients do not experience the same length of life and quality of life as their age-matched peers or other cancer survivors.
When NSCLC is detected at an early stage (IA to IIIA), the tumor is resected. The resection is followed by chemotherapy for larger tumors and in case the tumor has spread to the lymph nodes (stages II and IIIA). Patients in stage I receive no further treatment. Although these patients have a good prognosis based on tumor staging, a large percentage of patients develop metastases within several months or years. The consequence is a short survival time after resection. For this group of patients, follow up treatment would be beneficial. On the other hand, a substantial number of patients is cured and have a long survival period. For this group of patients, follow up treatment brings no benefit but only the side effects associated with the treatment. The options for further treatment are chemotherapy or targeted therapy with a kinase inhibitor like gefitinib. Side effects of chemotherapy are severe and also a rather mild therapy like treatment with gefitinib can have very unpleasant side effects. Therefore, it is no option to subject all persons diagnosed with lung cancer to adjuvant therapy after surgery.
There remains a pressing need for methods that provide good clinical predictions of the progression of NSCLC. These methods would enable the identification of NSCLC patients at an early stage, and more specifically provide an early determination of the prognosis of NSCLC. Additionally NSCLC patients with a poor survival prognosis might benefit from specific adjuvant therapies whereas other therapies might be more beneficial for NSCLC patients with a good survival prognosis.
The present invention aims at providing methods and devices for determining the survival prognosis of patients suffering from NSCLC. The present invention also aims to provide methods and devices for predicting the response of a patient diagnosed with NSCLC to a medicament.